Cooling system for internal combustion engines



Oct. 4, 1932. WALD 1,880,539

COOLING SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed NOV. 18, 1.929

, Y gmmntoz aktozmq Patented Oct. 4, 1932 ream FRANK A. WALD, or LnMoYNE, PENNSYLVANIA COOLING SYSTEM FOR INTERNAL COMBUSTION ENGINES Applicationifiled November 18, 1929. SerialNb. 408,100.

This invention relates to cooling systems especially adapted for use in connectionwith internal combustion engines,

Theinvention forming-the subject of this 5, application contemplates reliable and auto- 'matic means by which the flow andvelocity of cooling fluid through an internal combustion engine is controlled by, and'is proportionalto thetemperature of the cooling-fluid,

to the end that a more uniform temperature of the entire cooling system is maintained. Among the other advantages of such a control olthe flow of cooling fluid will be found increased velocity of'such fluid atperiods of operation when increased velocity is desired,

a higher operating temperature which is conducive to fuel economy, a reduction in-radiator :area, less distortion of'cylinder walls, and a diminishedtendency for the walls of gopthe fluid passages-to become foulediwith accumulations of scale and'the-like.

Another feature of the inventionresides in the adaptability of the same to the cooling systems of engines without elaborate departure from present construction and operating methods, it being noted in this CODIIQCUOII that the invention may be=applied to an engine either during manufacture or at any time thereafter;

Other objectsand advantages will be apparent during the. course of. the following description. V

In the accompanying drawing forming a, part of this application'and in which like numerals are employed to designate like parts throughout the same,

Figure 1 is a' fragmentary side elevation of an internal combustion engine equipped.

with the improved'cooling system,parts of the former and latter belngvshown 1111 section, -F1 TL1I'8 2 1s a. sectional view throu h a thermostat andassociated valve, the view illustrating a constantly-open by-pass for the circulation of the. cooling fluid regardless of the position of the thermostat operated valve, Figure 3 is a vertical sectional view through a relief valve embodied in the mvention.

In the drawing wherein for the purpose The thermostat 14 intended to be posi- I tioned at or-adjacent, to the outlet from the: water picket 6- might now be saiclto be 0011- ventionaIiand has connection with a valve'16 by'vvhich the flow of water from the engine to the header 7 is controlledi Such control: is,.of course, brought about by the temperature'of'the cooling fluidacting against the; thermostat 14 with the result'that arisein the temperature to a. predetermined value, such for eXample,-,as 185 will result, in the movement of thevalve 16 to open position.

l/Vhen the valve 16 occupies anopen posisuihcient cross sectional area toallow of. the free flow of fluid under pressure from-the pump-9 A. valve casing 20 is shown to be incorporated in the line of flow of the cooling fluid from the engine to the radiator and isiprovided with a valve element 22 having connection with asecond thermostat 24: adjusted to respond to a temperature somewhat high- 'erthan that at which the thermostat 14; op-

erates. For example it has been said that the thermostat 14 may be adjusted to open the valve 16 at approximately 135 Fahrenheit. Now, the thermostat 24 may be adjusted to open the valve element 22 atpostion, the fluid passage thus produced is of i sibly 150 to allow of the greatest flow of fluid of which the systemis capable.

The valve casing 20 is shown to be pro--- nature' of radial ports, which ports are confluid art-temperatures below that required to openthe valve element 22.

vided with a bypass 26 that may be'in thei stantly open to allowof a restricted flow'of It is important to observe that the fluid conducting capacity of the by-pass 26 is less than that of the fluid conducting passage associated with the valve 16, so that when the :hermostat 14 is open and the valve 22 has, as yet, remained unopened, the flow of cooling fluid, and consequently the velocity thereof, is restricted. lVith the valve 16 thus opened the descent of the cooling fluid through the radiator is by gravity aided by the suction effect of the pump 9.

The invention forming the subject of this application contemplates a cooling system sealed or isolated from the atmosphere exvvZept when it is necessary to relieve an abnormally high pressure resulting-from the failure of some part of the system on the as sociated internal combustion engine.

In explaining the sealing feature, attention is invited to Figures land 3 in which it is illustrated that the vent pipe 40 extending into the header 7 has the inlet thereof con trolled by a spring closed valve 42, the spring controlling the valve element 42 being of sufficient powerto resist the pressure increase incident to'the opening of the valve 22 in response to a predetermined rise in the temperature, of the circulating cooling fluid. More specifically, the spring closed valve 42 may be arranged to open under the influence of steam generated as an incident to improper operation of some part of the system, such, for example, as the pump or driving means therefor.

By thus normally sealing the system, changes in altitude will have no effect on the boiling point of the coolingfluid as distinguished from an open or vented cooling system in which the cooling fluid will boil at a high altitude at a lower temperature than the same fluid would boil in the same open system at sea level or other low altitude.

Figure 1 illustrates that an expansion tank may be attached to the dash or other convenient place on the car at a level preferably above that of the header 7. Communication is established between the expansion tank 60 and the fluid conducting means of the cooling system by a tube 62 which has, by way of illustration, been shown to communicate with the water jacket 6. V

In operation, when the motor is operating at normal load, the temperature of the cooling fluid will be of a value below that required to operate the thermostat 24 and the associated valve 22. Hence, there will be'a restricted flow through the fiXedby-pass openings, and, as pre riously suggested, the flow of cooling fluid through the tubes 30 will be by gravity aided by the slight suction efiect created by the pump 9. 7

Now, for the purpose of illustration, let it be assumed that the requirements on the motor areincreased materially, such, for example as when the motor isrequired to propel the vehicle on which it is mounted up a long steep grade with the throttle fully open or nearly so. The fulfillment of such a requirement is, of course, accompanied by an increase in the temperature of the cooling fluid, and this in turn, operates through the thermostat 24 to-bring about the unseatin'g of the valve 22 and the opening of the fluid passage previously closed, thereby permitting maximum velocity and flow of. the cooling fluid through the casing 20 and in fact through the entire system;

The opening or unseating of the valve 22 will result in an'increased pressure in the header 7 so that a greater volume of fluid is forcedthrough the radiator core to the end that the return of the lower-normal operating temperature is accomplished. Concurrently with the diminution in the temperature of the circulating fluid a retarded flow of circulating fluid will again prevail. The spring associated with the valve 42 is of sufficient strength to resist the pressure in the header? as a result of the unseating of the valve 22.

Thus, the automatically variable velocity of cooling fluid willbe recognized as of value in preventin both overcooling and overheating of cooling fluid. Also, such automatic variation in the velocity of cooling fluid makes possible a reduction in radiator area,

andhence, a higher temperature of fluid necessitating a higher velocity on the part of the'fluid. The higher mean temperature of the cooling fluid has the effect of increased efiiciency by reasonof the lower fuel consumption.

Furthermore, the automatically variable I pansion of the cooling fluid as a result of temperature increases thereof, all without open in thesystem to the atmosphere.

T-Iaving thus described the invention, what is claimed is:

1. The combination of an engine havinga jacket for a cooling fluid, a radiator having connection with said jacket, a thermostat having a valve controlling the flow of fluid between the jacket and the radiator, there being a constantly open by-pass allowing the flow of fluid between the acket and the radiator, and a second thermostat between the first named thermostat and jacket responsive to alower temperature than that at which the first thermostat operates, there being a valve associated with and operated by said second thermostat for controlling the entire circula Y tion of cooling fluid.

2. The combmation of an engine having av jacket for a cooling fluid, a radiator having connection with said acket, a thermostat having a valve controlling the flow of fluid between the jacket and the radiator, there being a constantly open by-pass allowing the flow of fluid between the jacket and the radiator, a second thermostat between the first named thermostat and jacket responsive to a lower temperature than that at which the first thermostat operates, there being a valve associated with and operated by said second thermostat for controlling the entire circulation of cooling fluid, and a vent pipe having a spring closed inlet located within said radiator and normally isolating the radiator and jacket from the atmosphere.

3. In a cooling system for internal combustion engines, a jacket adapted for the passage of a cooling fluid, a radiator, means establishing communication between said jacket and said radiator, a thermostat having a valve controlling communication between the acket and the radiator, a valve casing having a constantly open by-pass pro-' viding constricted communication between said jacket and said radiator, a valve for said casing, and a second thermostat connected to said second named valve and responsive to a temperature higher than that at which the first named thermostat operates, there being pressure responsive means normally isolating the radiator and jacket from the atmosphere.

4. In a cooling system for internal comin circuit with said jacket and said pump, heat responsive means for varying the velocity of the fluid traveling through the radiator and the water jacket, and an expansion tank having a single connection with the Water jacket and being out of the path of circulation of fluid through the jacket and the radiator. v

7. In a radiator, upper and lower headers and tubes joining the headers, a vent pipe open .at the lower end thereof to the atmos phere and havingan inlet located within said upper header, releasable means normally closing said inletand being responsive to the pressure withinthe upper header, and a heat responsive element throttling the flowof fluid through the radiator.

8. In a cooling system for internal combustion engines, a radiator having upper and lower headers and tubes joining the headers, and a vent pipe having an inlet within said upper header, said vent pipe extending below the upper header and being freely open at the lower end thereof to atmosphere, releasable spring pressed means normally clos-' ing said inlet and being responsive to the pressure prevailing within the upper header, a pump for circulating fluid under pressure through said radiator, and a heat responsive element throttling the flow of fluid through the radiator.

In testimony whereof I aflix my signature.

FRANK A. WALD.

bustion engines, a jacket adapted for the passage of a cooling fluid, a radiator, means establishing communication between said jacket and said radiator, a thermostathaving a valve controlling communication between the jacket and the radiator, a valve casing having a constantly open by-pass providing constricted communication between said jacket and said radiator, a valve for said casing, and a second thermostatconnected to said second named valve and responsive to a temperature higher than that at which the first named thermostat operates.

5. The combination of an internal combustion engine having a pump and a water jacket; a radiator in circuit with said jacket and said pump; heat responsive means for varying the velocity of the fluid traveling through the radiator and the water jacket; and releasable means including a vent pipe having its upper end disposed in the upper end of the radiator and its lower end arranged exteriorly of and below the radiator and opened to the atmosphere at said lower end, and a spring valve normally closing the upper end of the vent pipe for normally isolating the fluid passages through said radiator, said pump and said jacket from the atmosphere.

6. The combination of an internal combustion engine having a water jacket, a radiator 

